On a current telecommunications network, there are many complex network devices, such as a router, a gateway, a switch, a firewall, and various types of servers. These devices separately support various types of network protocols, so as to implement interworking between network elements. Each device internally includes a packet forwarding module and various types of protocol control modules. In such a distributed deployment manner of control modules, deployment and management of a network are very complex, and in order to modify or update a control parameter, a network operator must separately operate each device.
In order to implement deployment flexibility and manageability of a network element, a software-defined network (SDN) concept is put forward in the industry. An SDN decouples control logic of the network element from a forwarding function, and deploys the control logic in a centralized manner, so that control and maintenance on a network can be simply implemented by operating a device on a control plane, so as to increase management efficiency of the network, and further simplify a device on a forwarding plane, which facilitates implementation of high performance and reusability of a forwarding device. Currently, an SDN idea is widely applied to a data center network and the telecommunications network, and a network based on the SDN idea is referred to as a network in a control and forwarding decoupled architecture.
On the network in the control and forwarding decoupled architecture, a controller is responsible for determining a forwarding action (such as forwarding, discarding, modifying a packet header, encapsulating, or decapsulating) of a service flow according to a feature of a packet (such as an IP quintuple, an Ethernet frame header, or a VLAN ID), and delivering a corresponding flow entry (including flow matching information (such as an IP quintuple or an Ethernet frame header) and an action that is correspondingly performed) to a forwarder, and the forwarder acquires and stores the flow entry, and performs a corresponding action on a subsequent packet conforming to the flow entry, so as to forward the packet.
In the prior art, each packet that cannot match any flow entry stored in a flow table may trigger one packet reporting message. Therefore, before the forwarder receives a flow entry installation message and successfully installs a flow entry, packets of a same flow also trigger multiple packet reporting messages.
For example, in a scenario of transmitting some packets of a large data volume, for example, burst transmission of a user packet, or simultaneous switching of a large quantity of users to a new forwarder, the forwarder may simultaneously receive a large quantity of user packets belonging to a same flow, which causes a large quantity of concurrent packet reporting messages. These packet reporting messages not only consume computing resources of the forwarder and the controller, but also occupy signaling transmission resources, which, for example, causes a failure to transmit the flow entry installation message, and further causes more packet reporting messages, making a control interface of an entire system be in an overload state.